【作者】 曹智丽；

【导师】 让蔚清；

【作者基本信息】 南华大学 ， 卫生毒理学， 2005， 硕士

【摘要】 目的:本课题拟从体内动物实验、体外胚胎培养、细胞水平和分子水平探讨甲醛(Formaldehyde,FA)的生殖发育毒性,阐明其机理,为进一步研究甲醛对机体的远期效应和制定甲醛安全性评价标准提供实验依据。 方法:体内动物实验应用经胎盘遗传毒性试验观察甲醛对胎肝血微核率和胎肝染色体畸变率的影响。体外实验是将孕8.5天龄的昆明种小鼠脱颈处死,分离胚胎,采用全胚胎培养技术(whole embryo culture, WEC),将其置入含有不同浓度甲醛(0,3,9,27,81μmol/L)的大鼠即刻离心血清(immediately centrifugal serum, ICS)中旋转培养48小时,利用光学显微镜、解剖显微镜、中性红活体染色、组织切片HE染色及流式细胞仪等技术,观察甲醛对体外培养小鼠胚胎生长发育和组织器官形态分化的影响;为了研究甲醛生殖发育毒性的预防方法,在ICS中加入VitC,观察VitC对甲醛诱导胚胎生长发育毒性的干预作用;应用分光光度法观察甲醛对胚胎组织谷光甘肽(glutathion, GSH)含量和脂质过氧化产物丙二醛(malondialdehvde, MDA)含量的影响以分析其机制。 结果: 1.甲醛可通过胎盘屏障诱导胎鼠的染色体损伤。 2.甲醛能影响体外器官形成期的昆明种小鼠胚胎生长发育,具有一定的胚胎毒性,呈剂量-效应关系和时间-效应关系,以神经管闭合不全、体位翻转不全、脑部形态异常、心脏发育迟缓等畸形为特征;甲醛可致VYS及胚胎神经管、脑组织、心脏等结构明显受损,各浓度组胚胎畸形部位细胞经流式细胞仪检测发现甲醛可引起小鼠胚胎细胞周期发生变化,且出现典型的亚二倍体凋亡峰;中性红活体染色结果发现,甲醛染毒组,胚胎脑部、眼、鳃弓、心、肢芽、体节、尾部等部位出现大量的死亡细胞。 3.甲醛能引起胚胎组织中GSH含量下降和脂质过氧化产物MDA含量升高。更多还原

【Abstract】 Objiective: To observe the reproductive and developmental toxicity and to explorethe possible mechanisms of formaldehyde on mouse embryos in vitro.Methods: In vivo animal experiment: to conduct micronucleus and chromosomeaberration experiments with the fetal liver blood of the mice from the different groups, in order to observe the rate of MN and the rate of chromosome aberration. In vitro experiment: the postimplantation whole embryo culture (WEC) system was used to explore the effects of formaldehyde on cultured embryos in vitro. The 8.5 day isolated kun-Ming mice embryos (3~5 somites) at organogenetic stage were co-cultured for 48 hours in immediately centrifugal serum (ICS) with formaldehyde (final concentration of formaldehyde: 0, 3, 9, 27, 81μmol/L). To explore the characteristic of reproductive and developmental toxicity and their mechanisms of formaldehyde, the following techniqued were used in the study: neutral red staining were used to detect cell death ; flow cytometry were used to analyse the effects of cell cycle and the rate of apoptosis; Light microscope were used to observe damaged on structure of visceral yolk sac (VYS) and cultured embryos; The contents of GSH and MDA in embryo tissue were measured by relative detection kits; When 100μg/ml VitC was added to the culture medium along with formaldehyde, VitC could intervene effectively the developmental toxicity of formaldehyde on mouse embryos in vitro.Results:1. Formaldehyde could penetrate placental barrier and result in a significant impairment on the chromosome in fetal mouse.2. Formaldehyde could cause damage to embryonic development and there were dose-effect relationships and time-effect relationships in vitro. The major abnormalitied included abnormal nervous system (small forbrain and midbrain, open neural tube), heart (retarded heart , pericardial edema), abnormal flexions, small更多还原